1. Field of the Invention
The present invention relates to a method and apparatus that is of particular utility in cementing operations associated with oil and gas well exploration and production. More specifically the present invention provides an improvement to cementing operations and related operations employing a plug or ball dropping head and wherein plugs can be employed to pump cement into larger diameter casing.
2. General Background of the Invention
Patents have issued that relate generally to the concept of using a plug, dart or a ball that is dispensed or dropped into the well or “down hole” during oil and gas well drilling and production operations, especially when conducting cementing operations. The following possibly relevant patents are incorporated herein by reference. The patents are listed numerically. The order of such listing does not have any significance.
TABLEPAT. NO.TITLEISSUE DATE3,828,852Apparatus for Cementing Aug. 13, 1974Well Bore Casing4,427,065Cementing Plug Container Jan. 24, 1984and Method of Use Thereof4,624,312Remote Cementing Plug Nov. 25, 1986Launching System4,671,353Apparatus for Releasing a 4,671,353Cementing Plug4,722,389Well Bore Servicing ArrangementFeb. 2, 19884,782,894Cementing Plug Container with Nov. 8, 1988Remote Control System4,854,383Manifold Arrangement for use Aug. 8, 1989with a Top Drive Power Unit4,995,457Lift-Through Head and SwivelFeb. 26, 19915,095,988Plug Injection Method and ApparatusMar. 17, 19925,236,035Swivel Cementing Head with Aug. 17, 1993Manifold Assembly5,293,933Swivel Cementing Head with Mar. 15, 1994Manifold Assembly Having Remove Control Valves and Plug Release Plungers5,435,390Remote Control for a Plug-Jul. 25, 1995Dropping Head5,758,726Ball Drop Head With Rotating RingsJun. 2, 19985,833,002Remote Control Plug-Dropping HeadNov. 10, 19985,856,790Remote Control for a Plug-Jan. 5, 1999Dropping Head5,960,881Downhole Surge Pressure Reduction Oct. 5, 1999System and Method of Use6,142,226Hydraulic Setting ToolNov. 7, 20006,182,752Multi-Port Cementing HeadFeb. 6, 20016,390,200Drop Ball Sub and System of UseMay 21, 20026,575,238Ball and Plug Dropping HeadJun. 10, 20036,672,384Plug-Dropping Container for Jan. 6, 2004Releasing a Plug Into a Wellbore6,904,970Cementing Manifold AssemblyJun. 14, 20057,066,249Plug-Dropping Container for Jan. 6, 2004Releasing a Plug into a Wellbore8,256,515Method and Apparatus for Dropping Sep. 4, 2012a Pump Down Plug or Ball